When an inflatable such as a float, evacuation slide, or slide raft is used with a helicopter or aircraft, it is extremely important that the inflatable be properly positioned with respect to the craft to insure that it will function as intended. Positioning tubes or logs, inflatable from the same source as the inflatable, have been used both with respect to helicopter floats and evacuation slides. For example, refer to U.S. Pat. No. 3,598,215 assigned to the same assignee as this application.
In prior systems of the type, unrestricted openings have been provided between the inflatable and the positioning log with the same source of pressurized fluid used to inflate both. Thus when a load was applied to the inflatable, it would deform and be opposed by an equal resultant bearing load. With open communication between the inflatable and the log, the pressure in both remained essentially constant under load. Without any appreciable pressure increase in the log under load, the required contact area to maintain equilibrium increased as the applied load increased. As a result, the positioning log was either required to be larger and thus heavier to properly position the inflatable or a costly complex contoured shape was required.